Cattle Country: New research will enable greater use of cover crops on the Prairies, including grazing
The following article was written by Peter Frohlich, National Centre for Livestock and the Environment (NCLE), University of Manitoba. It was originally published in Cattle Country in September 2024.
Cover crops are important elements in regenerative agriculture, and therefore play an important role in achieving sustainable food production systems. Farm management surveys have reported an increase in their use nationally. Yet in Manitoba and Saskatchewan the practice of growing cover crops has increased at a slower pace when compared to Eastern Canada and the United States. According to the 2020 Prairie Cover Crop Survey Report, environmental factors like a shorter growing season and limited fall soil moisture on the prairies limit opportunities to plant cover crops prior to seeding or post-harvest. To address the challenges, researchers from the University of Manitoba and the South East Research Farm (Redvers, SK) have partnered on a project funded by The Foundation for Food and Agriculture Research, AgMission, and PepsiCo. The goal of this project is to develop and accelerate the adoption of climate smart agriculture (CSA) practices like the use of shoulder season cover crops (crops grown between a cash crop harvest and the planting of the next cash crop) in Canada’s eastern Prairies.
Cover crops, soli health and cattle production
Cover crops are annual or perennial plant species or a mixture of species. They are seeded with the intent to “cover” the ground and improve the soil. They may include a blend of warm-season and cool-season plants, grasses or cereals, legumes, and Brassica plant species (cruciferous vegetables). Planting cover crops contributes to climate resilient agriculture systems and mitigates climate change. They protect the soil from erosion and contribute to soil organic matter. Cover crops improve soil biological, chemical, and physical properties which enhances soil health. They have the potential to lower greenhouse gas emissions (GHG) through reduced use of tillage, reduced soil nitrogen losses, and increased carbon sequestration. They can also supress weeds, increase biodiversity and create new opportunities for integrating crop and livestock systems.
Cover crops also contribute to cattle production systems thanks to their potential value as a high-quality forage source. They can be grazed, baled or used for silage. Cattle consume forages including those from cover crops, converting them to high quality protein. In addition, soil health is improved as nutrients in manure reduce the need for commercial fertilizers and increase plant growth including grassland crops, creating feed for livestock while completing the circular bioeconomic cycle. Grazing these crops in grain cropping systems can extend the grazing season, contribute to an increased economic return and diversify agricultural production systems. In related research, Emma McGeough and Yvonne Lawley with the University of Manitoba found that intercropping Italian ryegrass and hairy vetch with corn can meet the dietary requirements for heifers.
Developing strategies for growing cover crops on the prairies
During the three-year project that started in the fall of 2023, researchers are exploring planting shoulder season cover crops at the time of annual cash crop seeding or in-crop. The method is called companion-seeding. It involves seeding lower-statured cover crop species along with the primary field crop during spring seeding or broadcast interseeding during the growing season. The strategy can be successful and attractive to farmers on the prairies because it eliminates the need for a separate cover crop seeding pass during the harvest season, allows field crops to grow with minimal competition from the cover crop, and maximizes the window for cover crop growth giving prairie farmers an additional option to incorporate cover crops into their rotation.
Researchers are working with farmers in Manitoba’s Red River Valley and southeastern Saskatchewan to validate and scale up the CSA practices. They are quantifying their impact on crop yield, grain quality, soil health and fertility, on environmental services and on GHG emissions. Cattle grazing is also incorporated into the system. This fall, farmers participating in on-farm trials who are comparing Italian ryegrass and fall rye as intercropped cover crops with canola are planning to let the cover crop grow for late fall grazing.
Goal of the project is to accelerate adoption of CSA practices
The project is designed to combine research and on-farm implementation in an innovative way to help accelerate adoption of CSA practices. The research team is co-developing new practices with farmers through workshops, interviews, and on-farm trials to better understand farmer perspectives and challenges they encounter when implementing new practices. Farmer perspectives will be incorporated into the scientific research process. Co-developed research findings will be made available through a range of knowledge sharing techniques, such as web-based platforms and field day events.
The research team includes:
Co-Principle Investigators:
- Lana Shaw, Executive Director and Research Manager, South East Research Farm
- Yvonne Lawley, Associate Professor, Department of Plant Science, University of Manitoba
- Luke Struckman, Principal Consultant, Resilient Agriculture Solutions
Other University of Manitoba Researchers:
- Francis Zvomuya, Professor, Department of Soil Science
- Afua Mante, Assistant Professor, Department of Soil Science
- Alejandro Costamagna, Acting Department Head and Professor, Department of Entomology